Optical scopes, such as rifle scopes, and other optical sighting systems are typically equipped with at least one adjustment mechanism such that a shooter can accommodate for various conditions that can cause the point-of-impact of a fired bullet to vary compared to an originally set point-of-aim, such as the ballistic properties of a bullet, environmental conditions (altitude, humidity, wind, etc.), and the distance to the target. Adjustment mechanisms may provide movement of the reticle with respect to the image that is created by the objective system (e.g., first focal plane) or the objective and the erector system (e.g., second focal plane). Knowing or estimating the environmental conditions and other factors influencing the point-of-impact, the shooter can adjust the reticle position so that the expected point-of-impact will be coincidental with a chosen feature within the reticle.